Background:
Thrombophilia testing is frequently ordered in the inpatient setting. However, testing is costly and can be misleading in the setting of acute thromboembolism or concurrent anticoagulation use. Furthermore, hereditary thrombophilias do not predict a clinically significant increase in VTE recurrence.
Methods:
We conducted an educational intervention with a randomized cross-over design for Internal Medicine interns at a major academic center during academic year 2014. Interns were randomized into two groups which received an hour-long interactive session either during the first or second half of the academic year (early and late intervention, respectively). The lecture focused on evidence-based guidelines regarding thrombophilia workups. We then assessed for intern ordering habits for thrombophilia before and after the intervention.
Thrombophilia testing was defined as assays for: factor V Leiden, prothrombin G20210A mutation, antithrombin III, protein C or S, lupus anticoagulant, beta-2 glycoprotein 1 IgM/IgG, anticardiolipin IgM/IgG, dilute Russell viper venom time, and the JAK2 V167F mutation. We defined criteria for test appropriateness using current published evidence, reviewed by a senior hematologist.
We performed manual chart review of all inpatient thrombophilia tests from June 2013 to December 2015. We analyzed 1) intervention group ordering, 2) intern ordering during the prior academic year (historical control) and 3) non-intervention services ordering during the intervention year (contemporaneous control).
Results:
In total, we reviewed 2151 orders and found 934 inappropriate (43.4%). The two intervention groups placed 147 orders within their 18 month study period.
The early intervention group demonstrated a decrease in inappropriate ordering (40.0% pre-early intervention, 36.4% pre-late intervention, and 16.1% post-intervention for both groups). A similar trend was noted in the late intervention group (40.0% pre-early intervention, 38.1% pre-late intervention, and 23.3% post-intervention for both groups). Together, both groups demonstrated a decrease in inappropriate ordering from the pre-intervention (39.2%) to post-intervention (24.0%) period (Table 1, Figure 1).
Both historical and contemporaneous control groups did not demonstrate improvement with the former ordering 35.7%, 33.78%, 40.0% inappropriately and the latter ordering 42.2%, 44.1%, 42.8% inappropriately over their respective time periods.
Conclusions:
During the period after the early intervention but before the late intervention, there was no difference in ordering patterns between the intervention groups. However, both early intervention and late intervention groups had improved significantly over time during the final follow-up period, an improvement which was not seen in either control groups. These findings suggest that education on thrombophilia ordering may improve inpatient ordering practices.
